Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, so the description doesn't need to argue safety, and instead it adds a genuinely useful behavioral quirk: 'Beds24 answers HTTP 200 with validToken=false for a bad token.' That warns the agent not to treat a 200 as success. It stops short of documenting caching, rate limits, or the exact response shape, so 4 rather than 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, each carrying distinct information: what is checked, why to call it, and the HTTP 200 pitfall. The purpose is front-loaded and the endpoint reference is a compact trailing detail.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no parameters, no output schema, and annotations covering the safety profile, the description supplies the remaining needed context by listing the returned fields (scopes, owner id, expiry, restriction) and the misleading-status caveat. An agent has everything required to call and interpret it.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so the baseline of 4 applies; there is no argument surface the description could or should explain.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Check the configured Beds24 token') and enumerates exactly what is reported: validity, scopes, owner id, expiry, and property restriction. This is clearly distinguishable from every sibling, which all deal with bookings, rooms, or messages rather than auth state.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'A cheap way to confirm setup and see which scopes are granted' gives a clear use context for diagnosis/setup verification. It does not name a when-not or an alternative, but no sibling overlaps this capability, so the gap is minor.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.